diff --git a/src/Serializer/ItemNormalizer.php b/src/Serializer/ItemNormalizer.php
index c426584aa8..1cc8452a98 100644
--- a/src/Serializer/ItemNormalizer.php
+++ b/src/Serializer/ItemNormalizer.php
@@ -68,6 +68,17 @@ public function denormalize(mixed $data, string $class, ?string $format = null,
             }
         }
 
+        // See https://github.com/api-platform/core/pull/7270 - id may be an allowed attribute due to being added in the
+        // overridden getAllowedAttributes below, in order to allow updating a nested item via ID. But in this case it
+        // may not "really" be an allowed attribute, ie we don't want to actually use it in denormalization. In this
+        // scenario it will not be present in parent::getAllowedAttributes
+        if (isset($data['id'], $context['resource_class'])) {
+            $parentAllowedAttributes = parent::getAllowedAttributes($class, $context, true);
+            if (\is_array($parentAllowedAttributes) && !\in_array('id', $parentAllowedAttributes, true)) {
+                unset($data['id']);
+            }
+        }
+
         return parent::denormalize($data, $class, $format, $context);
     }
 
@@ -107,4 +118,14 @@ private function getContextUriVariables(array $data, $operation, array $context)
 
         return $uriVariables;
     }
+
+    protected function getAllowedAttributes(string|object $classOrObject, array $context, bool $attributesAsString = false): array|bool
+    {
+        $allowedAttributes = parent::getAllowedAttributes($classOrObject, $context, $attributesAsString);
+        if (\is_array($allowedAttributes) && ($context['api_denormalize'] ?? false)) {
+            $allowedAttributes = array_merge($allowedAttributes, ['id']);
+        }
+
+        return $allowedAttributes;
+    }
 }
diff --git a/tests/Fixtures/TestBundle/Entity/Issue6225/Bar6225.php b/tests/Fixtures/TestBundle/Entity/Issue6225/Bar6225.php
new file mode 100644
index 0000000000..6a5b06df56
--- /dev/null
+++ b/tests/Fixtures/TestBundle/Entity/Issue6225/Bar6225.php
@@ -0,0 +1,71 @@
+<?php
+
+/*
+ * This file is part of the API Platform project.
+ *
+ * (c) Kévin Dunglas <dunglas@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace ApiPlatform\Tests\Fixtures\TestBundle\Entity\Issue6225;
+
+use ApiPlatform\Metadata\ApiResource;
+use Doctrine\ORM\Mapping as ORM;
+use Symfony\Component\Serializer\Annotation\Groups;
+use Symfony\Component\Uid\Uuid;
+
+#[ORM\Entity]
+#[ORM\Table(name: 'bar6225')]
+#[ApiResource]
+class Bar6225
+{
+    public function __construct()
+    {
+        $this->id = Uuid::v7();
+    }
+
+    #[ORM\Id]
+    #[ORM\Column(type: 'symfony_uuid', unique: true)]
+    #[Groups(['Foo:Read'])]
+    private Uuid $id;
+
+    #[ORM\OneToOne(mappedBy: 'bar', cascade: ['persist', 'remove'])]
+    private ?Foo6225 $foo;
+
+    #[ORM\Column(length: 255)]
+    #[Groups(['Foo:Write', 'Foo:Read'])]
+    private string $someProperty;
+
+    public function getId(): Uuid
+    {
+        return $this->id;
+    }
+
+    public function getFoo(): Foo6225
+    {
+        return $this->foo;
+    }
+
+    public function setFoo(Foo6225 $foo): static
+    {
+        $this->foo = $foo;
+
+        return $this;
+    }
+
+    public function getSomeProperty(): string
+    {
+        return $this->someProperty;
+    }
+
+    public function setSomeProperty(string $someProperty): static
+    {
+        $this->someProperty = $someProperty;
+
+        return $this;
+    }
+}
diff --git a/tests/Fixtures/TestBundle/Entity/Issue6225/Foo6225.php b/tests/Fixtures/TestBundle/Entity/Issue6225/Foo6225.php
new file mode 100644
index 0000000000..7f625901db
--- /dev/null
+++ b/tests/Fixtures/TestBundle/Entity/Issue6225/Foo6225.php
@@ -0,0 +1,71 @@
+<?php
+
+/*
+ * This file is part of the API Platform project.
+ *
+ * (c) Kévin Dunglas <dunglas@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace ApiPlatform\Tests\Fixtures\TestBundle\Entity\Issue6225;
+
+use ApiPlatform\Metadata\ApiResource;
+use ApiPlatform\Metadata\Patch;
+use ApiPlatform\Metadata\Post;
+use Doctrine\ORM\Mapping as ORM;
+use Symfony\Component\Serializer\Annotation\Groups;
+use Symfony\Component\Uid\Uuid;
+
+#[ORM\Entity()]
+#[ORM\Table(name: 'foo6225')]
+#[ApiResource(
+    operations: [
+        new Post(),
+        new Patch(),
+    ],
+    normalizationContext: [
+        'groups' => ['Foo:Read'],
+    ],
+    denormalizationContext: [
+        'allow_extra_attributes' => false,
+        'groups' => ['Foo:Write'],
+    ],
+)]
+class Foo6225
+{
+    public function __construct()
+    {
+        $this->id = Uuid::v7();
+    }
+
+    #[ORM\Id]
+    #[ORM\Column(type: 'symfony_uuid', unique: true)]
+    #[Groups(['Foo:Read'])]
+    private Uuid $id;
+
+    #[ORM\OneToOne(inversedBy: 'foo', cascade: ['persist', 'remove'])]
+    #[ORM\JoinColumn(nullable: false)]
+    #[Groups(['Foo:Write', 'Foo:Read'])]
+    private Bar6225 $bar;
+
+    public function getId(): Uuid
+    {
+        return $this->id;
+    }
+
+    public function getBar(): Bar6225
+    {
+        return $this->bar;
+    }
+
+    public function setBar(Bar6225 $bar): static
+    {
+        $this->bar = $bar;
+
+        return $this;
+    }
+}
diff --git a/tests/Functional/NestedPatchTest.php b/tests/Functional/NestedPatchTest.php
new file mode 100644
index 0000000000..52fc1c756c
--- /dev/null
+++ b/tests/Functional/NestedPatchTest.php
@@ -0,0 +1,78 @@
+<?php
+
+/*
+ * This file is part of the API Platform project.
+ *
+ * (c) Kévin Dunglas <dunglas@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace ApiPlatform\Tests\Functional;
+
+use ApiPlatform\Symfony\Bundle\Test\ApiTestCase;
+use ApiPlatform\Tests\Fixtures\TestBundle\Entity\Issue6225\Bar6225;
+use ApiPlatform\Tests\Fixtures\TestBundle\Entity\Issue6225\Foo6225;
+use ApiPlatform\Tests\RecreateSchemaTrait;
+use ApiPlatform\Tests\SetupClassResourcesTrait;
+
+class NestedPatchTest extends ApiTestCase
+{
+    use RecreateSchemaTrait;
+    use SetupClassResourcesTrait;
+
+    protected static ?bool $alwaysBootKernel = false;
+
+    public static function getResources(): array
+    {
+        return [Foo6225::class, Bar6225::class];
+    }
+
+    public function testIssue6225(): void
+    {
+        if ($this->isMongoDB()) {
+            $this->markTestSkipped();
+        }
+
+        $this->recreateSchema(self::getResources());
+
+        $response = self::createClient()->request('POST', '/foo6225s', [
+            'json' => [
+                'bar' => [
+                    'someProperty' => 'abc',
+                ],
+            ],
+            'headers' => [
+                'accept' => 'application/json',
+            ],
+        ]);
+        static::assertResponseIsSuccessful();
+        $responseContent = json_decode($response->getContent(), true);
+        $createdFooId = $responseContent['id'];
+        $createdBarId = $responseContent['bar']['id'];
+
+        $patchResponse = self::createClient()->request('PATCH', '/foo6225s/'.$createdFooId, [
+            'json' => [
+                'bar' => [
+                    'id' => $createdBarId,
+                    'someProperty' => 'def',
+                ],
+            ],
+            'headers' => [
+                'accept' => 'application/json',
+                'content-type' => 'application/merge-patch+json',
+            ],
+        ]);
+        static::assertResponseIsSuccessful();
+        static::assertEquals([
+            'id' => $createdFooId,
+            'bar' => [
+                'id' => $createdBarId,
+                'someProperty' => 'def',
+            ],
+        ], json_decode($patchResponse->getContent(), true));
+    }
+}